Question

Anoxygenic phototrophic bacteria do not utilize:

• A. $Water$
• B. $C{O}_2$
• C. $H_{2}S$
• D. $Thiosulphate$

Answer 1

The correct option is A $Water$

There are several bacteria that cannot oxidize water. Thus, they perform anoxygenic photosynthesis that depends on mostly Hydrogen Sulphide. Anoxygenic photosynthesis reaction is represented as:
$C{O}_2+H_{2}S\underset{light}{\overset{energy}{\to }}sugars+sulphur+water$